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답안 #733711

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
733711 2023-05-01T08:21:06 Z GrindMachine Transport (COCI19_transport) C++17
104 / 130
 362 ms 65536 KB 
// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<pll> adj[N];
vector<ll> adjc[N];
vector<ll> a(N);
vector<bool> rem(N);
vector<ll> subsiz(N);

ll dfs1(ll u, ll p) {
    subsiz[u] = 1;
    for (auto [v, w] : adj[u]) {
        if (v == p or rem[v]) conts;
        subsiz[u] += dfs1(v, u);
    }
    return subsiz[u];
}

ll dfs2(ll u, ll p, ll nodes) {
    for (auto [v, w] : adj[u]) {
        if (v == p or rem[v]) conts;
        if (subsiz[v] > nodes / 2) {
            return dfs2(v, u, nodes);
        }
    }

    return u;
}

vector<ll> sumup(N), mnprefup(N);
vector<array<ll, 3>> here[N];
ll guy;

void dfs3(ll u, ll p, ll sumdown, ll mnprefdown) {
    here[u].pb({sumup[u], mnprefup[u], mnprefdown});

    // vector<ll> vals = {sumup[u], mnprefup[u], mnprefdown};
    // debug(guy);
    // debug(u);
    // debug(vals);
    // cout << endl;

    for (auto [v, w] : adj[u]) {
        if (v == p or rem[v]) conts;
        sumup[v] = a[v] - w + sumup[u];
        mnprefup[v] = min(a[v] - w, a[v] - w + mnprefup[u]);
        dfs3(v, u, sumdown + a[u] - w, min(mnprefdown, sumdown + a[u] - w));
    }
}

ll build(ll u, ll p) {
    ll nodes = dfs1(u, -1);
    ll centroid = dfs2(u, -1, nodes);

    if (p != -1) {
        // cout << p << " " << centroid << endl;
        adjc[p].pb(centroid);
    }

    rem[centroid] = 1;
    sumup[centroid] = 0;
    mnprefup[centroid] = 0;
    guy = centroid;

    dfs3(centroid, -1, 0, 0);

    for (auto [v, w] : adj[centroid]) {
        if (rem[v]) conts;
        build(v, centroid);
    }

    return centroid;
}

ll get(vector<array<ll, 3>> v) {
    vector<ll> vals;
    for (auto [sum, mnprefup, mnprefdown] : v) {
        vals.pb(mnprefdown);
    }

    sort(all(vals));

    ll res = 0;

    for (auto [sum, mnprefup, mnprefdown] : v) {
        if (mnprefup < 0) conts;
        ll cnt = vals.end() - lower_bound(all(vals), -sum);
        if (mnprefdown >= -sum) {
            cnt--;
        }
        res += cnt;
    }

    return res;
}

vector<ll> nodes[N];
ll ans = 0;

void dfs4(ll u, ll p) {
    vector<array<ll, 3>> big;
    big.pb(here[u].back());
    here[u].pop_back();

    nodes[u].pb(u);

    trav(v, adjc[u]) {
        if (v == p) conts;
        dfs4(v, u);
        vector<array<ll, 3>> curr;
        trav(node, nodes[v]) {
            curr.pb(here[node].back());
            big.pb(here[node].back());
            nodes[u].pb(node);
            here[node].pop_back();
        }

        nodes[v].clear();
        nodes[v].shrink_to_fit();

        ans -= get(curr);
    }

    // debug(u);
    // trav(ar, big) {
    //     vector<ll> v(all(ar));
    //     debug(v);
    // }
    // debug(get(big));
    // cout << endl;

    ll temp = get(big);
    ans += temp;

    // debug(temp);

    // if (u == 4) {
    //     trav(ar, big) {
    //         vector<ll> v(all(ar));
    //         debug(v);
    //     }

    //     debug(temp);
    // }

    // ans += get(big);
}

void solve(int test_case)
{
    ll n; cin >> n;
    rep1(i, n) cin >> a[i];
    rep1(i, n - 1) {
        ll u, v, w; cin >> u >> v >> w;
        adj[u].pb({v, w}), adj[v].pb({u, w});
    }

    ll root = build(1, -1);
    dfs4(root, -1);

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Subtask #1
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 13 ms 14312 KB Output is correct
2 Correct 14 ms 14200 KB Output is correct

Subtask #2
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 15316 KB Output is correct
2 Correct 19 ms 16044 KB Output is correct

Subtask #3
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 132 ms 40560 KB Output is correct
2 Correct 124 ms 38144 KB Output is correct

Subtask #4
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 172 ms 51112 KB Output is correct
2 Correct 205 ms 57244 KB Output is correct

Subtask #5
0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 181 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #6
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 104 ms 28268 KB Output is correct
2 Correct 55 ms 21484 KB Output is correct

Subtask #7
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 110 ms 29316 KB Output is correct
2 Correct 160 ms 36448 KB Output is correct

Subtask #8
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 261 ms 43468 KB Output is correct
2 Correct 217 ms 42440 KB Output is correct

Subtask #9
13.0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Correct 345 ms 53568 KB Output is correct
2 Correct 322 ms 53824 KB Output is correct

Subtask #10
0 / 13.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 362 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -